Lol, I'm playing FFX as I type=P. Haven't beaten yet, I had to start over when I got a PS3, but I'm at the part after I kill Seymore again and Tidus is talking to that Fayth kid that keeps showing up and he tells Tidus that he is a dream.
All the Jak games had sad endings. In Jak and Daxter you find out that Daxter will never be changed back, and once you beat the game, it's over. In Jak 2, you find out that Jak is never going back to the old place that he thought was his home. In Jak 3, I don't know, it just doesn't seem like a good way to end the series.
Tony Hawk's Underground was very sad. Your only friend turns into a jerk and gets rich off of your footage. You have to go back to your small little town of New Jersey. I don't know why, but small places make me depressed. What's even more depressing is that I can't play online anymore=(.
I haven't really beaten that many other games, other than Ratchet and Clank and Pacman World 2. I don't know why, I guess I just get bored too easily=P. I want to beat Resistance before Resistance 2 comes out, though, and I think I'm pretty close.